Caster

ABSTRACT

The invention relates to a caster ( 1 ) having a casting ladle ( 2 ), a distribution device ( 4 ), and a horizontally moveable transport belt ( 5 ) having side limitation elements ( 13, 14 ), wherein liquid metal, preferably steel, can flow out of the casting ladle ( 2 ) onto the distribution device ( 4 ), and from there can be applied to the horizontal transport belt ( 5 ), the side limitation elements ( 13, 14 ) of the horizontal transport belt ( 5 ) being adjustable over the width of the horizontal transport belt. The invention further relates to a corresponding method.

RELATED APPLICATIONS

This application is a continuation of application Ser. No. 12/733,062 filed Feb. 3, 2010 which is a national stage application of PCT application PCT/EP2008/006731 filed Aug. 13, 2008 which claims priority of German applications DE 10 2007 038 621.6 filed Aug. 16, 2007 and DE 10 2008 031 476.5 filed Jul. 3, 2008, all of the above-mentioned applications are incorporated herein by reference thereto.

DESCRIPTION

1. Technical Field

The invention relates to a caster for casting, in particular, a liquid steel on a horizontal conveyor belt according to preamble of claim 1 and to a method of operating a caster according to preamble of claim 8.

2. State-of-the-Art

In state-of-the art, known are casters in which liquid steel flows from a casting ladle in a distribution device and therefrom on a horizontal conveyor belt on which the liquid metal solidifies to a pre-strip and simultaneously is carried away and is cooled. This method is also known as a horizontal casting.

Corresponding casters are known in the state-of-the art and are disclosed in DE 198 52 275 or WO 97/06906.

The casters for a horizontal casting described above have a drawback that consists in that their width is fixed, and that a substantial modification of the installation is required in order to change the cast width of the horizontal conveyor belt and, thus, of the pre-strip, in case such modification is economically justified at all. To this end, typically a very extensive assembly and disassembly is necessary, and expensive components are needed, so that such change of an installation in width in any event, has little appeal. Correspondingly, for different cast widths, different horizontal casting installations are produced which then, on close examination, can be used to their full capacity.

This drawback results in that a change in an installation is relatively expensive and idle time is increased, or requires producing a second, third, or several installations, with an increased costs factor.

All in all, these solutions up to now are associated with increased costs and loss of time, which leads to an inflexible operation or to production losses of such casting installations.

DESCRIPTION OF THE INVENTION, OBJECT, SOLUTION, ADVANTAGES

It is an object of the present invention to provide a casting installation for casting, in particular, steel onto a horizontal conveyor belt, with which difficult requirements with regard to dimensions of to-be-cast pre-strips can be realized quickly and without large expenses.

According to the invention, this object is achieved, with respect to a caster, by providing a caster having a casting ladle, a distribution device and a horizontally displaceable conveyor belt having side limitation elements, in which liquid metal, preferably, steel flows from the casting ladle in the distribution and therefrom onto the horizontal conveyor belt, wherein the side limitation elements of the horizontal conveyor belt are adjustable over the width of the horizontal conveyor belt. Thereby, it can be advantageously achieved that the pre-strip, relevant for the casting process, can be formed variable in width. The adjustment can be effected advantageously mechanically or hydraulically with a corresponding servo element. Advantageously, the adjustment is reversible.

Advantageously, the distribution device is adjustable in width in direction of the width of the conveyor belt. Thereby, advantageously, the casting behavior and distribution behavior of the liquid metal on the conveyor belt can be controlled.

It is further expedient, when beneath the horizontal, conveyor belt stand/or above the horizontal conveyor belt, at least one tempering, e.g., cooling device is arranged and which serves for cooling a pre-strip displaceable with speed on the conveyor belt.

It is particularly advantageous when the at least one cooling device is variably adjustable in width in direction of the width of the conveyor belt.

It is further advantageous when the at least one cooling device is divided in width in cooling zones in direction of the width of the conveyor belt.

It is particularly advantageous when the cooling device has a plurality of cooling zones, of which at least two zones are edge zones which are turned on or off dependent on a to-be-cooled width.

According to the invention, the object of the invention, with respect to a method, is achieved with a method of operating a caster, in particular a caster having a distribution device and, in particular, a horizontally displaceable belt with side limitation elements, wherein a width of a cast product is determined and adjusted with side limitation elements adjustable in width at an angle of 90° to a cast direction.

This is particularly advantageous when the distribution device is arranged between the side limitation elements.

With another embodiment, it is also advantageous when the distribution device is located, in the cast direction upstream of the side limitation elements and the liquid metal flows head-first against the side limitation elements and narrows to a casting width by the side limitation elements.

Further advantages are disclosed in subclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

Below, the invention will be explained based on an embodiment shown in the drawings.

The drawings show:

FIG. 1 a cross-sectional schematic view of a caster;

FIG. 2 a plan schematic view of a cooling device with an adapted or adjustable width;

FIG. 3 a plan schematic view of a cooling device with an adapted or adjustable width;

FIG. 4 a plan schematic view of a cooling device with an adapted or adjustable width;

FIG. 5 a plan schematic view of a cooling device with an adapted or adjustable width;

FIG. 6 a plan schematic view of a cooling device with an adapted or adjustable width; and

FIG. 7 a plan schematic view of a cooling device with an adapted or adjustable width.

PREFERRED EMBODIMENT OF THE INVENTION

FIG. 1 shows a schematic cross-sectional view of a caster 1 in which the liquid steel or a liquid metal is poured from a casting ladle 2 into a tundish 3 and runs therefrom via a distribution device 4 onto a horizontal conveyor belt 5. The horizontal conveyor belt 5 is a driven belt that conveys further the metal solidified on the conveyor belt, such as a pre-strip 7, with a predetermined speed. To this end, there are provided rollers 6 about which the driven belt 5 circulate as a continuous belt.

Preferably, beneath the conveyor belt 5 and/or also above the conveyor belt 5 there are provided cooling devices 9 which serve for controlled and precise cooling of a cooled and solidified pre-strip 7 displaceable on the conveyor belt 5 with a certain speed. The cooling devices 9 are formed as, e.g., spray devices for spraying a cooling medium such as, e.g., water that is sprayed on or is applied to the conveyor belt and/or the pre-strip. The cooling device 9 can, e.g., can cool the heat-transmitting belt 5 itself, so that a solidified metal deposited on the conveyor belt 5 is cooled. Thereby, the heat of the pre-strip 7 is removed from the pre-strip by the sprayed or applied cooling medium.

Above the conveyor belt 5, there is provided an inert gas hood 8 that protects the pre-strip from the external atmospheric air. The inert gas hood 8 can also be positively supported on side limiting elements 13, 14 to prevent loss of heat.

The side limiting elements are shown only schematically.

FIGS. 2 through 7 show schematically a plan view of a caster 10 and in which essentially only the cooling device 11 located above and/or below the horizontally displaceable conveyor belt, the distribution device 12, and two side limiting elements 13, 14 are shown. The conveyor belt and the side limiting elements are shown only schematically.

In FIG. 2, it can be seen that the two side limiting elements 13 and 14 are located relatively closer to each other in comparison with the arrangement in FIG. 3. The distribution device 12 has, at its outlet, a width that corresponds approximately to the distance between the two side limitation elements. Thus, FIG. 2 shows an arrangement for a small strip width and in which the width of the outlet of the distribution device 12 approximately corresponds to the width of the conveyor belt.

Contrary to this, in the caster of FIG. 3, the width is adjusted to a greater width so that the width of the produced pre-strip, i.e., the distance between the side limitation elements 13, 14 is greater than the width of the distribution device 12 of the liquid metal at its outlet. The width of the distribution device 12 at its outlet is not changed in FIGS. 2 and 3.

In FIG. 4, both side limitation elements again are arranged relatively closer to each other in comparison with the arrangement of FIG. 5. The distribution device 12 has a width greater than the distance between the both side limitation element 13, 14. The caster in FIG. 4 shows an arrangement for a small strip width.

Contrary to the arrangement in FIG. 4, the caster in FIG. 5 is adjustable to a greater width so that the width of reproduced pre-strip, i.e., the distance between the side limitation elements 13, 14 is as wide or smaller than the width of the distribution device 12 of the liquid metal at its outlet. The width of the distribution device 12 at its outlet is not changed in FIGS. 13 and 14. The width of the distribution device 12 can, alternatively, be changeable in another embodiment.

All in all, FIG. 2-5 show, respectively, a caster 10 with side limitation elements 13, 14 with an adjustable distance therebetween. The distribution device 12 for distributing the liquid metal on the conveyor belt of the caster can be formed with an outlet having an adjustable width. The width of the pre-strip between the side limitation elements 13, 14 can be smaller, equal to, or wider than the width of the distribution device 12 at its outlet. By adjustment of the width of the distribution device 12, streams with different mass can be brought onto the conveyor belt of the caster in which, the width of the distribution device 12 with respect to the stream mass can be adjusted, taking into account the width of the pre-strip.

If the distance between the side limitation elements 13, 14 is greater than the width of the distribution device 12 at its outlet, the distributed liquid metal also flows in the width direction on the conveyor belt, being distributed to the strip width of the pre-strip determined by the distance between the side limitation elements 13, 14.

If the distance between the side limitation elements 13, 14 is smaller than the width of the distribution device 12, the exiting liquid metal that flows in the width direction strikes against the side limitation elements 13, 14 on the conveyor belt and spreads over the entire strip width determined by the width of the side limitation elements 13, 14.

If the distance between the side limitation elements 13, 14 is essentially equal to the width of the distribution device 12, the exiting fluid metal flows essentially parallel to the belt width on the conveyor belt and spreads over the entire belt width determined by the width of the side limitation elements.

In addition to the adjustment of the width of the side limitation elements 13, 14 of the conveyor belt and/or the distribution device 12, the cooling device 11 can also be adjustable to a variable width, so that the cooling device 11 can be adjusted to a variable width with regard to its cooling capacity or cooling temperature. The cooling device 11 can be divided in different cooling zones over the width of the belt of the caster so that, e.g., edge cooling zones 15 at the edges of the cooling device 11 can be turned on or off in case they are needed or not, based on a selected width of a to-be-cast pre-strip. FIGS. 6 and 7 show such an embodiment in which the cooling device 11 is adjusted to different active widths. In FIG. 6, the edge zones 15 are, respectively, turned off, and in FIG. 7, the edge zones of the cooling device 11 are activated, i.e., they are used for cooling the pre-strip. Activation and deactivation of the edge cooling zones 15 is effected, preferably, dependent on the adjusted width of the pre-strip, i.e., dependent on the distance between the side limitation elements 13, 14.

According to the invention, it is particular advantageous when the adjustment of the width of a to-be-cast material can be reversibly carried out. To this end, the adjustment of the distance between the side limitation elements 13, 14 is reversibly carried out. Advantageously, in one of the embodiments, the cooling with the cooling device with cooling zones is also adjustable to the necessary width. In addition, it is advantageous when the adjustment of the width of the distribution device 12 is reversibly carried out. According to a particular advantageous embodiment, all three, the width of spacing of the side limitation elements 13, 14, the width of the distribution device 12, and the width of the coding device 12, 15 are reversibly adjustable. It is particularly advantageous that this reversible adjustment can be effected and changed during operation, i.e., on line.

LIST OF REFERENCE NUMERALS

-   1 Caster -   2 Casting ladle -   3 Tundish -   4 Distribution device -   5 Conveyor belt -   6 Roller -   7 Pre-strip -   8 Inert gas hood -   9 Cooling device -   10 Caster -   11 Cooling device -   12 Distribution device -   13 Side limitation element -   14 Side limitation element -   15 Cooling zone, edge zone 

1. A method of operating a caster having a horizontally displaceable conveyor belt provided with side limitation elements, and a tundish arranged at one end of the conveyor belt above a plane of the conveyor belt for supplying molten metal onto the conveyor belt, the method comprising the steps of providing a distribution device having an adjustable width and located beneath the tundish in the plane of the conveyor belt for horizontally delivering the molten metal from the tundish onto the conveyor belt; and variably adjusting a width between the side limitation elements over a width of the conveyor belt at an angle of 90° to a cast direction, while material is being cast between the side limitation elements, in accordance with the width of the distribution device and with a predetermined width of a cast product.
 2. The method according to claim 1, wherein the step of providing the distribution device includes locating the distribution device between the side limitation elements.
 3. The method according to claim 1, including the step of providing an inert gas hood over the conveyor belt for protecting the cast product.
 4. A caster (1), comprising: a horizontally displaceable conveyor belt (5); a casting ladle (2) provided at one end of the conveyor belt (5); a tundish (3) located beneath the casting ladle (2) and above a plane of the conveyors belt (5) for feeding molten metal on the conveyor belt (5); a distribution device (4) located beneath the tundish (3) in the plane of the conveyor belt (5) with which molten metal is horizontally delivered from the tundish (3) onto the conveyor belt (5), the distribution device having an adjustable width; side limitation means (13, 14) for variably adjusting a width of a pre-strip displaceable on the conveyor belt (5) over the width of the conveyor belt at an angle of 90° to a cast direction, while the pre-strip is being cast between side limitation elements of the side limitation means, in accordance with the width of the distribution device and a predetermined width of a cast product; at least one cooling device (9) located beneath the horizontal conveyor belt (5) and which cools a pre-strip displaceable by the conveyor belt (5), the at least one cooling device (9, 11) being adjustable in width in the cast direction of the conveyor belt (5) while the pre-strip is being cast, the at least one cooling device being divided in width thereof in direction of the conveyor belt in cooling zones including at least two edge zones which are turned on or off dependent on a width of a to-be-cooled pre-strip; and an inert gas hood (8) located above the horizontal conveyor belt for protecting the pre-strip.
 5. The caster according to claim 2, wherein the distribution device is located between the side limitation elements. 